Ian Evatt believes the quality of Bolton Wanderers set pieces are 'not good enough' and must improve.
The Whites suffered a defeat on the road against Grimsby Town over the weekend, but remain in the automatic promotion places with four games of their League Two season to go.
Against the Mariners, Bolton struggled to cope with the aerial deliveries and set pieces launched by Grimsby into the box, aimed towards the likes of James Hanson and Lenell John-Lewis.
A look at the figures from football statistics website WhoScored.com shows that Wanderers have some of the highest goals scored from open play this season, but rank among the lowest for strikes from set plays.
And Evatt admits Bolton's lack of potency from these situations is a source of frustration, particularly when other teams in the division can look so dangerous from this aspect of the game.
But over the weekend, Evatt believes the state of the Blundell Park pitch suited the hosts better with their style of play when compared to Bolton's, which slowed Wanderers and their passing game down.
He said: "They’re not good enough and it’s frustrating. Every set piece that comes in our box, a lot of oppositions look a threat and then we have opportunities and we just don’t make the most of it. It’s not like we don’t work on it.
"We just need to be better at it and maybe we’re lacking a bit of belief.
"Having said that, the way we create chances from open play is excellent and when you’re playing on a surface like this, it’s easier being Grimsby than Bolton Wanderers with the way they play.
"It simplifies their game and we have to be extremely precise, take extreme care because of the pitch, take more touches than we normally would have to, which slows us down.
"Having said that, we still created lots and lots of opportunities that we just didn’t take.”